Sparticle spectrum and phenomenology in split supersymmetry: some possibilities

TL;DR

This paper explores the spectrum and phenomenology of split supersymmetry, emphasizing how different SUSY breaking mechanisms influence collider signals and particle properties, including the role of a new fermion and the behavior of gluinos.

Contribution

It analyzes how specific SUSY breaking details affect the sparticle spectrum and collider phenomenology in split supersymmetry, introducing a new fermion and alternative scenarios for gaugino propagation.

Findings

A new fermion $_X$ influences low-energy phenomenology.

Collider signals include associated production of the light neutral Higgs.

Gluinos can be heavy and short-lived in certain models.

Abstract

We investigate the split supersymmetry (SUSY) scenario recently proposed by Arkani-Hamed and Dimopoulos, where the scalars are heavy but the fermions are within the TeV range. We show that the sparticle spectrum in such a case crucially depends on the specific details of the mechanism underlying the SUSY breaking scheme, and the accelerator signals are also affected by it. In particular, we demonstrate in the context of a braneworld-inspired model, used as illustration in the original work, that a new fermion $\psi_X$, arising from the SUSY breaking sector, is shown to control low-energy phenomenology in several cases. Also, SUSY signals are characterised by the associated production of the light neutral Higgs. In an alternative scenario where the gauginos are assumed to propagate in the bulk, we find that gluinos can be heavy and short-lived, and the SUSY breaking scale can be free of cosmological constraints